Electrodeposition of nickel



United States Patent 3,254,007 ELECTRODEPOSITION 0F NICKEL Otto Kai-dos, Red Bank, N.J., assignor to Hanson-Van yinkle-Munning Company, a corporation of New ersey No Drawing. Filed Feb. 5, 1963, Ser. No. 256,228 14 Claims. (Cl. 20449) This invention relates to electroplating and, more particularly, to electrodepositing nickel from an aqueous acidic nickel plating bath. The invention is based on the discovery that N-cyanosulfonamides which contain the structural configuration when incorporated in a nickel electroplating bath, either as the sole brightener or in conjunction with various Class I carrier brightness or Class II leveling brightening addition agents (or both), are remarkably effective for promoting the formation of nickel deposits which are bright over a very wide current density range and which also possess satisfactory mechanical properties, particularly low internal stress and fair ductility.

Only relatively small quantities of these N-cyanosul fonamides are required in the plating bath, for, in general, concentrations as low as 0.01 millimole per liter have been found to be effective. In many cases, however, at least 0.1 millimole per liter should be employed to secure the full benefit of its presence in the bath.

There appears to be no sharp upper limit on the concentration of these N-cyanosulfonamides, but there is generally no advantage in employing more than 25 millimoles per liter, and in most plating baths substantially the full benefit of their presence is achieved with an amount in the range from about 0.1 to about 10 or even 5 millinroles per liter.

Any N-cyanosulfonamide which contains the structural configuration may be selected for inclusion in the plating bath. Many of these N-cyanosulfonamides produce fully bright nickel deposits over the entire, or almost the entire,- current density range of the Hull Cell panel, yielding bright nickel deposits with low internal stress. Moreover, I have also found that these N-cyanosulfonamide brighteners impart to the plating solution high tolerances to contamination with zinc and copper, which usually occurs upon plating zinc-base die castings.

A preferred process according to this invention for producing low-stress, ductile nickel deposits comprises electrodepositing nickel from an aqueous solution of at least one nickel salt in which there is dissolved from about 0.01 to about 25 millimoles per liter of a watersoluble N-cyanosulfonamide having a structure represented by the formula in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals, (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo-, sulfoalkyl-, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation substituent of the group consisting of hydrogen, the alkali metals, magnesium, cobalt, and nickel, and n is an integer from 1 to 3.

Particularly satisfactory results have been obtained by using in the plating bath such N-cyanosulfonamides as benzene-N-cyanosulfonamide, p-bromobenzene-N-cyanosulfonamide, 3,4-dichlorobenzene N-cyanosulfonamide, p-toluene-N cyanosulfonamide, benzyl-N cyanosulfonamide, p-acetamidobenzene-N-cyanosulfonamide, m-ben zenedi-(N-cyanosulfonamide), diphenylsulfone 3,3'-di- (N-cyanosulfonamide), or their alkali metal, magnesium, cobalt, or nickel salts.

The N-cyanosulfonamides are much more effective brighteners than the related sulfonarnides which do not contain the N-cyano group, such as benzene sulfonamide, p-toluenesulfonamide, N-chloro p-toluenesulfonamide, m-benzenedisulfonarnide. As a haze remover in bright nickel baths, e.g. in a Watts nickel bath containing benzene sulfonic acid and 2-'butyne-l',4-diol, o-sulfobenzoic imide (sacch-arin) is about equally effective as benzene-N-cyanosulfonamide but o-sulfobenzoic imide produces low-current discoloration in presence of 0.15 'gram per liter of zinc, While the bcnzene-N-cyanosulfonamide does not.

Preparation of the N-cyanosulfonamides may be accomplished by reacting a sulfonyl halide, generally the chloride, with a stoichiometric amount of hydrogen cyanamide, and twice the stoichiometric amount of aqueous alkali metal hydroxide.

In contrast to sulfur free 'cyano compounds, such as ethylenecyanohydrin or hydrogen cyanamide, many N- cyanosulfonamides yield bright nickel deposits with low internal stress when used as the sole addition agents to a nickel bath, but do not exert any appreciable leveling effect. -If in addition to brightness, leveling is desired, the N-cyanosulfonamides may be used in the plating bath in conjunction with leveling agents, e.g. water-soluble acetylenic compounds, such as propargyl alcohol,- 2- butyne 1,4-diol or 1,4-di-(5-hydroxyethoxy) -2-butyne; olefinic glycols, such as 2-butene-l,4-diol; nitriles such as ethylenecyanohydrin; hydrogen cyanamide; coumarin; and quinolinimum compounds.

While any water-soluble acetylenic brightening compound may be employed in a nickel plating bath conjointly with an N-cyanosulfonamide, particularly satisfactory results have been obtained using (it-substituted acetylenic compounds having a structure represented by the formula in which each of R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroxy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl groups, and each of R, and R, are substituents of the group consisting of hydroxy, alkoxy, carboxy-sub stituted alkoxy, formoxy, alkanoxy, halogen, and polyoxy groups, Where R is a substituted-alkyl group having the above-illustrated structuralconfiguration, then the acetylenic compound is termed an a,u'- disubstituted -acetylenic compound, since both carbon atoms vicinal to the same acetylenie bond contain either the same or a different functional group. The compounds listed'in Table I are examples of various 'a-substituted acetylenic compounds which may be used successfully in plating baths containing an N-cyanosulfonamide bright- 2-b-utyne-1,4-diol reacts with ethylene oxide in the presence of a base to form a 1,4-di-(hydroxypolyethoxy)- ener. These acetylenic-compounds are preferably used in concentrations from about 0.1 to about 25 millimoles 10 and with epichlorohydnn to form a 1,4-d1-[hydroxypolyper liter.

TABLE I.a-SUBSTIT UTED ACETYLENIC COMPOUNDS 1'3: R;C C(IJ-R1 Compound R1 R: Ra Ra 3-butyne-L2-diol H H OH 3-methyl-1-butyn-3-ol. 0 Hz 0 Ha H 0 H 3-methyl-1-pentyn-3-ol C 1H; 0 H; H O H 2-pr0pyn-1-ol H H OH 2 ,4-hexadiyne-L6-dlol. H -H C E CCH: O H O H 1-butyn-3-ol -0H, H H OH 1,2-di- (fl-hydroxyethoxy)-3- CH;O CH:CH|OH --H H O CHzCHaOH butyue. 3-(fl-hydroxy-y-chloropropoxy)- CzH5 CH| -H CHaCl 3-methyl-4-pentyne.

O.CH1CHOH Table II sets forth examples of a,a'-disubstituted acetylenic compounds which, when used in the plating bath in conjunction with an N-cyanosulfonamide brightener, yield bright nickel electroplates which possess good ductility, have low internal stress and have excellent leveling.

(fi-chloromethyethoxyfl-2-butyene, the structure of which is represented by the formula TABLE II.-a,a'-DISUBSTITUTED ACETYLENIC COMPOUNDS Gompound R1 R, R R; Ra Ra 2-butyne-1,4-diol -H H -H --H OH OH 2,5-dlmethyl-3-hexyne-2,5-d1ol -CH: CH; --CH: CH; 0H H 2,5-Diphenyl-3-hexyne 2,5-diol 'C6H5 -CH: CH: CaHl OH ---OH 4-methoxy-2-butyn- -01 --H -H -H H OH CHa 1,4-dl-(fl-hydroxyethoxy)-2-butyne- H H H H OCH:CH:OH OCH1OH:OH 4,7-di-(fl-hydroxy-v-chloropropoxy)- C;H --CH, -CH, C H 0 CHgCHgOH -O CHgOEhOH 4,7-d1methyl-5-decyne.

4 v OHiCl 013101 1 ,4-dl-(fl-hydr0xy- -chloroprop0xy)- H H H H v 0 CHICH OH O CHM JHOH 2-butyne. I l-(B-hydroxyethoxy)-2-butyn-4-ol -31 H -H -H -OH -0CH2CH2OH A I cruel 011,01 -(lsy y-vpr p xy)- 0 OH H H -o on OCH:( 3HOH OOH:CHOH

1,4,7-octatriyne. 4-ehloro-2-butyn-1-ol H -]1 -H -H C1 action of 2 -butyne-1,4-diol with ethylene oxide and with epichlorohydrin.

These adducts readily dissolve in 65 x and y in both formulas being integers from 1 to 8. The leveling effect of both of these reaction products in combination with N-cyanosulfonamides in nickel plating baths is especially pronounced.

In addition to the use of the acetylenic brighteners in the plating solution, the usual Class I carrier sulfooxygen brightening "additives may also be employed in the bath together with the N-cyanosulfonamides. These sulfo-oxygen carrier brighteners, which are generally used in concentrations in the range fromabout to about '80 grams per liter (and preferably in the range from about 1 to about 20 grams per liter), are unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, heterocyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, mag- Grams/liter Nickel sulfate, NiSO -6H O 300 Nickel chloride, NiCl -6H O 60 Boric acid, H 30 42 Plating operations in each example were carried out in Example I Nickel was electrodeposited from the basic Watts bath to which had been added 0.8 gramper liter '(ca. 4 millirnoles per liter) of sodium benzene N cyanosulfonamide, yielding a fully bright nickel deposit, with little or no leveling, over the entire current densityrange of the Hull Cell panel. The addition of 0.2 gram per liter of zinc (as zinc sulfate) had no deleterious effect.

When (i) 0.08 to 0.32 gram per liter of 2-butyne-l,4- diol, (ii) 0.08 to 0.12 gram per liter of 1,4-di-(a-hydroxyethoxy)2 butyne, (iii) 0.4 to 0.8 gram per liter of the reaction product of eqruimolar quantities of 2-butyne-1,4- diol and sodium bisulfite (of. U.S. Patents 3,002,902 and 3,002,903), (iv) 0.06 gram per liter of 1,4-(diethylamino)-2 bu-tyne (ii-hydrochloride, (v) 1 to 1.6 gram-s per liter of Q-butene-lA-diol, (vi) 0.04 to 0.06 gram per liter of hydrogen cyanamide, (vii) 0.08 gram per liter of acetylcyanamide, or (viii) 0.08 gram per liter of N-ethylquinolinium iodide were added to the bath containing sodium benzene-N-cyanosulfonamide, the resultant nickel deposits were bright over the entire current density range .of the Hull Cell and were appreciably smoother than the basis metal to which the particular deposit was applied.

Example 11 When nickel was electrodeposited from the standard Watts solution described above, to which had been added 9 grams per liter of sodium benzenesulfonate, and 0.27 gram per liter of 2-butyne-l,4-diol, the resultant deposit was marred by a haze in the low current density areas. Upon the addition of 0.2 gram per liter of sodium benzene N-cyanosulfonamide to this bath, this haze was completely eliminated. Addition of 0.15 gram per liter of zinc (as zinc sulfate) to the bath did not result in any deleterious effect to the appearance of the electroplate.

Example III When 0.8 gram per liter (ca. 2.4 millimoles per liter) of disodium un-benzenedi-(N-cyanosulfonimide) was added to thebasic Watts solution, the resultantnickel deposit was bright over the entire current density range of the Hull Cell panel. Cooperation with 0.1 gram per liter of 2-butyne-1,4-diol, or with the acetylenic diol and 4 grams per liter of sodium benzenesul-fonate, was excellent, with addition of 0.2 gram per liter of zinc (as the sulfate) having no harmful eifect on the appearance of the electroplate.

Example IV The addition otf 0.8 gram per liter of sodium p-bromobenzene-N-cyanosulfonarnide to the basic Watts bath produced a fully bright nickel electrodeposit over the entire current density range of the Hull Cell panel. Cooperation with the leveling agent, 2-butyne-l,4-diol (0.16 gram per liter), was satisfactory.

56 Example V The addition of 0.8 gram per liter of sodium 3,4-dichlorobenzene-N-cyanosulfonamide to -a Watts nickel bath produced a bright nickel deposit over the whole current density range of the Hull Cell with the exception of the very low current density areas (below 10 amp/ sq. ft), Where the deposit was somewhat dark. At a pH of 3.2 this low current density darkness disappeared. Further addition of 0.24 gram per liter of 2-butyne-1,4-diol produced fully bright and strongly leveled deposits.

Example VI The addition of 0.8 gram per liter of sodium p-to luene- N-cyanosulfonamide to a Watts nickel bath gave a bright nickel deposit over almost the whole current density range of the Hull Cell panel at 60 C., and a pH of 3.8. Even better results were obtained at a pH of 3.2. Cooperation with 4 grams per liter of sodium benzenesul fonate and 0.16 gram per liter of 2-butyne-l,4-dio.l was, in a purified Watts nickel bat-h, as satisfactory as with the corresponding sodium benzene-N-cyanosulfonamide; however, the benzene derivative tolerated 0.1 gram per liter (and more) of zinc ion (ph=3.8 and 3.2), while the toluene derivative gave a discolored low current density are-a in the presence of a like amount of zinc.

Example VII When 0.4 gram per liter of sodium benzyl N-cyanosulfonamide was added to a Watt-s nickel bath C., pH=3.8, air agitation), the resultant nickel deposit was fully bright, non-leveling with the exception of one hazy spot, 0.8 gram per liter of the additive producing a larger haze area. When 0.1 gram per liter to 0.2 gram per liter of this additive was added to a Watts nickel bath (60 C., pH=3.8) containing 9 grams per liter of sodium benzenesulfon-ate and 0.24 gram per liter of 2-butyne 1,4-diol, the slight center haze was completely eliminated.

Example VIII To a mixture of 0.1 mole (23.37 g.) N-acetylsulfanilyl chloride, 0.1 mole cyanamide (50% aqueous solution) and 8 ml. of Water, was slowly added dropwise a solution of 0.2 mole (8 g.) of sodium hydroxide in 16 ml. of water. The temperature was maintained at 45 C. Since the reaction product did not separate out easily, it was diluted with Water to 200 ml. and treated with 2 g. of activated carbon. Addition of 16 milliliters per liter of this prodnot, equivalent to 8 millimoles per liter, produced a fully brig-ht deposit over almost the whole current density range of the Hull Cell panel.

Example X Addition of only 0.8 millimole per liter of N-acetylsulfanilylcyanamide removed the residual hazes from the nickel deposit obtained from a Watts nickel bath (pH :38) containing 4.5 grams per liter of sodium benzenesulfonate and 0.24 gram per liter of 2-butyne-1,4-diol. The non-acetylated sulfanilylcyanam-ide had a much stronger embrittling effect and a much weaker brightening effect than the N-acety-lated derivative.

7 Example XI nickel bath containing 4 grams per liter sodium benzenesulfonate and 0.16 gram per liter of 2-butyne-l,4-diol was very effective in brightening local haze areas on the Hull Cell panel and thus promoting the production of a leveling nickel deposit which was fully bright over the whole current density range of the Hull Cell.

Example XII To 0.5 mole hydrogen cyanamide (50% aqueous solution) and 1.0 mole sodium hydroxide (25% aqueous solution), 0.25 mole of sulfuryl chloride, SO Cl were added dropwise and with stirring and cooling, the temperature being maintained at 45 C. The reaction mixture was then diluted to 400 ml. Addition of 1.6 milliliters per liter of this reaction product (equivalent to 1 millimole per liter of'SO C1 to a' Watts nickel bath containing 4.5 grams per liter of sodium benzenesulfonate gave bright nickel deposits over almost the entire current density range of the Hull Cell, instead of the essentially semibright deposit obtained with benzenesulfonate by itself.

Example XIII To a mixture of 0.1 mole (21.8 grams) of trichloromethanesulfonyl chloride, 0.1 mole hydrogen cyanamide (50% aqueous solution) and 8 ml. of Water was added 0.2 mole of sodium hydroxide (8 grams in 24 ml. of

water), with stirring and cooling, the temperature be- Example XIV Addition of 0.2 to 0.4 gram per liter of sodium 2- thiophene-N-cyanosulfonamide to a Watts nickel bath gave nickel deposits which were bright, but not leveled, up to 60 to 90 amperes per square foot. In presence of 8 grams per liter of sodium benzenesulfonate and 0.16 gram per liter of 2-butyne-1,4-diol, addition of only 0.1 gram per liter, or about 0.5 millimole per liter) of the thiophene derivative was sufiicient to remove residual hazes and produce a fully bright, leveled nickel deposit over the whole current density range of the Hull Cell. The resultant bath had excellent tolerance to 0.1 gram per liter of zinc contamination.

Example XV 0.1 mole of m-benzenedisulfonyl chloride and 0.1 mole of hydrogen cyanamide were allowed to react in pres- 'ence of 0.4 mole of aqueous sodium hydroxide. The reaction product was diluted to a volume of 200 ml., treated with some activated carbon, and filtered. Addition of 8 milliliters per liter (corresponding to 4 millimoles per liter) of this reaction product to a Watts nickel bath (60 C., pH=3.8) produced a bright nickel deposit over the entire current density range. Further addition of leveling agents; such' as 2-butyne-1,4-diol (0.16 gram per liter) or hydrogen cyanamide (0.06 gram per liter) produced bright and leveled nickel deposits.

In the foregoing examples of the invention, the' N- cyanosulfonamides were successfully employed alone and in combination with various lacetylenic and Class I carrier brighteners in the standard Watts nickel electroplating bath, which is prepared by dissolving nickel sulfate, nickel chloride, and boric acid in water. Similar advantages are also attained when the N-cyanosulfonamide is used in other types of aqueous acidic nickelelectroplating baths. For example, these N-cyan-osulfonamides are beneficial when used in high chloride. nickel baths, and in various other nickel plating baths based on using nickel sulfamate or nickel fluoborate as the principal nickel salt which is dissolved in an aqueous acidic solvent.

I claim:

1. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from about 0.01 to about 25 millimoles per liter of a water-soluble N-cyanosulfonamide which contains the structural configuration 2. The process for producing bright nickel deposits which compriseselectrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from about 0.01 to about 10 millimoles per liter of a water-soluble N-cyanosulfonamide having a structure represented by the formula 3. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from about 0.01 to about 10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, M-benzenedi (N-cyanosulfonamide), toluene-N-cyanosulfonamide, the halo-substituted derivatives of said N-cyanosulfonamides and the alkali metal, magnesium, cobalt, and nickel salts thereof.

4. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about 10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, mbenZene-di-(N-cyanosulfonamide) toluene N cyanosulfonamide, the halo-substituted derivatives of said N-cyanosulfonamides, and the alkali metal, magnesium, cobalt, and nickel salts thereof; and (b) from about 0.1 to about 25 millimoles per liter of a water-soluble leveling agent.

5. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about 10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, mbenzene di (N cyanosulfonamide), toluene-N-cyano sulfonamide, the halo-substituted derivatives of said N- cyanosulfonarnides and the alkali metal, magnesium, cobalt, and nickel salts thereof; (b) from about A to about 80 grams per liter of a water-soluble sulfooxygen compound of the group consisting of unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, heterocyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, magnesium, cobalt, and nickel salts of said acids and mononuclear aromatic sulfonamides and sulfonimides; and (c) from about 0.1 to about 25 millimoles per liter of a watersoluble leveling agent.

6. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about 25 millimoles per liter of a water-soluble N-cyanosulfonamide having a structure represented by the formula ii 1 R IS NC EN in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals, (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo, sulfoalkyl, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation substituent of the group consisting of hydrogen, the alkali metals, magnesium, cobalt, and nickel, and n is an integer from 1 to 3; and (b) from about A to about 80 grams per liter of a water-soluble sulfo-oxygen compound of the group consisting of unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, heterocyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, magnesium, cobalt and nickel salts of said acids, and mononuclear aromatic sulfonamides and sulfonimides.

7. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from about 0.01 to about 25 millimoles per liter of a water-soluble N-cyanosulfonamide having a structure represented by the formula in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals, (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo-, sulfoalkyl-, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation substituent of the group consisting of hydrogen, the alkali metals, magnesium, cobalt, and nickel, and n is an integer from 1 to 3; and (b) from about 0.1 to about 25 millimoles per liter of a leveling agent selected from the group consisting of (i) water-soluble acetylenic compounds, (ii) the bisulfite monoadducts of Water-soluble acetylenic compounds, (iii) Water-soluble olefinic compounds, (iv) hydrogen cyanamide, (v) acetyl-cyanamides, and (vi) quinolinium compounds.

8. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved from about 0.01 to about 25 millimoles per liter of a water-soluble N-cyanosulfonamide having a structure represented by the formula in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo-, sulfoalkyl-, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation substituent of the group consisting of hydrogen, the

10 alkali metals, ammonium, magnesium, and nickel, and n is an integer from 1 to 3; and (b) from about 0.1 to about 10 millimoles per liter of an ot-substituted acetylenic compound having a structure represented by the formula 1?: R3CEC(iJ-Rr R1! in which each of R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroXy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl groups, R is a substituent of the group consisting of hydrogen, halogen, alkyl, alkenyl, alkynyl, hydroxy-substituted and alkoXy-substituted alkenyl and alkynyl groups, and substituted-alkyl groups having the structural configuration in which each of R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroxy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl'groups, and each of R, and R, are substituents of the group consisting of hydroxy, alkoxy, carboxysubstituted alkoxy, formoxy, alkanoxy, halogen, and polyoxy groups.

9. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about 25 millimoles per liter of a Water-soluble N-cyanosulfonamide having a structure represented by the formula /i l RA' fiN-CEN in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals, (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo-, sulfoalkyl-, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation in which each of R R R and R are substituents of (b) from about A to about grams per liter of a Water-soluble sulfo-oxygen compound of the group consisting of unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, hetero cyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, magnesium, cobalt, and nickel salts of 1 1 said acids, and mononuclear aromatic sulfonamides and sulfonimides; and (c) from about 0.1 to about 10 millimoles per liter of a water-soluble acetylenic brightening compound.

11. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from -about 0.01 to about 25 millimoles per liter of a watersoluble N-cyanosulfonamide having a structure represented by the formula in which R is a radical selected from the group consisting of (i) alkyl and substituted-alkyl radicals, (ii) mononuclear and binuclear aromatic and alkyl-, sulfo-, halo-, sulfoalkyl-, haloalkyl-, acetamido-substituted aromatic radicals, and (iii) heterocyclic radicals, M is a cation substituent of the group consisting of hydrogen, the alkali metals, magnesium, cobalt, and nickel, and n is an integer form 1 to 3; (b) from about A to about 80 grams per liter of a water-soluble sulfo-oxygen compound of the group consisting of unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, heterocyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, magnesium, cobalt and nickel salts of said acids, and mononuclear aromatic sulfonamides and sulfonimides; and (c) from about 0.1 to about 10 millimoles per liter of an tat-substituted acetylenic compound having a structure represented by the formula in which each of R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroxy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl groups, R is a substituent of the group consisting of hydrogen, halogen, alkyl, alkenyl, alkynyl, hydroXy-substituted and alkoxy-substituted alkenyl and alkynyl groups, and substituted-alkyl groups having the structural configuration in which each of R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroxy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl groups, and each of R, and R, are substituents of the group consisting of hydroxy, alkoxy, carboxysubstituted alkoXy, formoxy, alkanoxy, halogen, and polyoxy groups.

12. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about'10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, m-benzenedi-(N-cyanosulfonamide), toluene-N-cyanosulfonamide, the halo-substituted derivatives of said N-cyanosulfonamides and the alkali metal, magnesium, cobalt, and nickel salts thereof; and (b) from about 0.1 to about millimoles per liter of a water-soluble acetylenic brightening compound.

13. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (at) from about 0.01 to about 10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, m-benzene-di- (N-cyanosulfonamide), toluene-N-cyanosulfonamide, the halo-substituted derivatives of said N-cyanosulfonamides and the alkali metal, magnesium, cobalt, and nickel salts thereof; (b) from about A to about grams per liter of a Water-soluble sulfo-oxygen compound of the group consisting of unsaturated aliphatic sulfonic acids, mononuclear and binuclear aromatic sulfonic acids, heterocyclic sulfonic acids, mononuclear aromatic sulfinic acids, the alkali metal, magnesium, cobalt, and nickel salts of said acids, and mononuclear aromatic sulfonamides and sulfon imides; and (c) from about 0.01 to about 10 millimoles per liter of a water-soluble acetylenic compound selected from the group consisting of propargyl alcohol, 2-butyne- 1,4-diol, 1-butyn-3-ol, 3-methyl-1-butyn-3-ol, a-polyoxy acetylenic compounds having a structure represented by the formula and a,a'-di(polyoxy) acetylenic compounds having a structure represented by the formula in which each of R R R and R are substituents of the group consisting of hydrogen, alkyl, alkenyl, alkynyl, and hydroxy-substituted and alkoxy-substituted alkyl, alkenyl, and alkynyl groups, R is a substituent of the group consisting of hydrogen, halogen, alkyl, alkenyl, alkynyl, hydroXy-substituted and alkoxy-substituted alkenyl and alkynyl groups, and substituted-alkyl groups having the structural configuration in which R, is a substituent of the group consisting of hydroxy, alkoxy, carboXy-substituted alkoxy, formoxy, alkenoxy, halogen, and polyoxy groups, and x and y are integers from 1 to 8.

14. The process for producing bright nickel deposits which comprises electrodepositing nickel from an aqueous acidic solution of at least one nickel salt in which there is dissolved (a) from about 0.01 to about 10 millimoles per liter of an N-cyanosulfonamide selected from the group consisting of benzene-N-cyanosulfonamide, m-benzene di-(N-cyanosulfonamide), toluene-N-cyanosulfonamide, the halo-substituted derivatives of said N-cyanosulfona-mides and the alkali metal, magnesium, cobalt, and nickel salts thereof; and (b) from about 0.01 to about 10 millimoles per liter of a water-soluble, u,a-di(polyoxy)- 2-butyne having a structure represented by the formula in which x and y are integers from 1 to 8.

References Cited by the Examiner UNITED STATES PATENTS 2,782,155 2/1957 Du Rose et al 204 49 2,994,648 8/1961 Du Rose 20449 3,002,904 10/1961 Foulke et al 20449 3,116,225 12/1963 Michael et al -1 20449 J. H. MACK, Primary Examiner. 

1. THE PROCESS FOR PODUCING BRIGHT NICKEL DEPOSITS WHICH COMPRISES ELECTRODEPOSITING NICKEL FROM AN AQUEOUS ACIDIC SOLUTION OF AT LEAST ONE NICKEL SALT IN WHICH THERE IS DISSOLVED FROM ABOUT 0.01 TO ABOUT 25 MILLIMOLES PER LITER OF A WATER-SOLUBLE N-CYANOSULFONAMIDE WHICH CONTAINS THE STRUCTURAL CONFIGURATION 